Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Administrative data

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1992
Report Date:
1992

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EU Method C.5 (Degradation: Biochemical Oxygen Demand)
Version / remarks:
84/449/EEC C.5
Biotic degradation: modified Sturm test
Deviations:
yes
Remarks:
1.5 L vessels rather than 3 L vessels
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
Constituent
Type:
Constituent
Type:
impurity
Type:
impurity
Type:
impurity
Test material form:
liquid

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
Bacteria collected from activated sludge of the sewage treatment plant of CH-4153 Reinach on 03/08/92. The pH after collection was 7.1 .
Duration of test (contact time):
28 d
Initial test substance concentrationopen allclose all
Initial conc.:
12.4 mg/L
Based on:
test mat.
Initial conc.:
22.4 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
CO2 evolution
Details on study design:
Vessels : 2 Liter flasks (dark brown glass), equipped with gas inlet and magnetic stirrer
Temperature: 22 +/- 2 degrees C
Duration: 28 days
Air: 25 ml/min purified from carbon dioxide.
Reference substance
Reference substance:
other: not specified but performed as expected

Results and discussion

% Degradation
Parameter:
% degradation (CO2 evolution)
Value:
25
Sampling time:
28 d
Details on results:
Theorteical CO2 pased on 12.4 mg/1 = 51.41 mg CO2/I.5 liter

Applicant's summary and conclusion

Interpretation of results:
not readily biodegradable
Conclusions:
There was 25% degradation after 28-days. After an inital lag in degradation, there was significant degradation during the final week of the study suggesting the test material would have continued to degrade.
Executive summary:

There was 25% degradation after 28-days.  After an inital lag in biodegradation, there was significant biodegradation during the final week of the study suggesting the test material would have continued to degrade.